Examples of List usage in Python.
As we know how to define lists in python from the post: http://ngelinux.com/lists-in-python/
However lists are used frequently in python and we should know how to play with them.
Lets see below program with various different ways to use lists.
List Examples
# 1. Define List
friends = ["Kevin", "Karen", "Jim", "OSCAR","TIDE"]
# 2. Printing a set of elements
print("1st to 3rd element")
print(friends[1:4])
print("\n")
# Negative index starts from back.
# Hence you can refer negative index also to read from last.
# 3. Print complete list
friends[1]="Mahesh"
print("All lists:")
print(friends)
# 4. Combining two lists
facebook_friends=["Moh", "Lui", "Santa", "Charlie"]
print(facebook_friends)
friends.extend(facebook_friends)
print("\nAll friends with added element at index 1 are: ")
# 5. Adding a new element at index 1
friends.insert(1,"NEWFRIEND")
print(friends)
# 6. Removing an element.
friends.remove("Kevin")
print("\nKevin friend removed:")
print(friends)
# 7. Check if an element exists in the list
print(friends.index("Santa"))
## print(friends.index("Kelly")) ## Throws an error as it doesn't exists.
# 8. Pop an element to remove it.
# Use sort to sort the list
friends.sort()
print(friends)
# 9. Empty List
friends.clear()
print("\nAll friends cleared:")
print(friends)
Output
/Users/saket/PycharmProjects/1helloworld/venv/bin/python /Users/saket/PycharmProjects/1helloworld/lists.py 1st to 3rd element ['Karen', 'Jim', 'OSCAR'] All lists: ['Kevin', 'Mahesh', 'Jim', 'OSCAR', 'TIDE'] ['Moh', 'Lui', 'Santa', 'Charlie'] All friends with added element at index 1 are: ['Kevin', 'NEWFRIEND', 'Mahesh', 'Jim', 'OSCAR', 'TIDE', 'Moh', 'Lui', 'Santa', 'Charlie'] Kevin friend removed: ['NEWFRIEND', 'Mahesh', 'Jim', 'OSCAR', 'TIDE', 'Moh', 'Lui', 'Santa', 'Charlie'] 7 ['Charlie', 'Jim', 'Lui', 'Mahesh', 'Moh', 'NEWFRIEND', 'OSCAR', 'Santa', 'TIDE'] All friends cleared: [] Process finished with exit code 0